This invention relates generally to improvements in a disposable absorbent garment intended to be used to receive or tending to receive discharge from the body, and in particular relates to disposable diapers, incontinent pads, and the like designed to be worn on the body and having a contractable thigh-encircling portion which conforms to the contours of the body and permits movement of the body while maintaining a seal with the body in motion. This invention further relates to means to secure such a garment to the body of the wearer and more particularly to means adapting the thigh-encircling portions of said garment to an adult leg configuration.
Absorptive devices such as disposable incontinent briefs are well-known in the art. These devices are used to absorb liquid from the human body and retain that liquid until the garment can be disposed of. Present disposable incontinent briefs are frequently flat composite sheets which are fitted to a wearer in the flat state or incorporate geometric folding to achieve a suitable body shape. A major in-use problem with such prior art articles is that gaps between the brief and the wearer's legs tend to develop due to the semi-rigid nature of the absorbent body, especially after the brief has been worn for some time, or during a period of activity when the garment is able to flex or shift on the wearer's body. These gaps permit leakage from a disposable garment, thereby creating damp outer clothing or bedding around the wearer.
Although these problems have been alleviated somewhat in the case of infant's diapers, the fitting of such a garment to an adult presents problems not found in the creation of a garment suitable for an infant.
First, since the legs of an infant characteristically form a substantial angle with the lateral line of the trunk of the body, it has been observed that a diaper having straight-line elastics such as those described in U.S. Pat. No. 3,860,003 issued to Buell on Jan. 14, 1975, can be secured to the infant's body by a single securement means on either side of the diaper. This is true because a circle drawn around the top portion of the diaper on the baby's body and a circle drawn around the thigh seal portion very nearly intersect at one tangent point, so that a single securement means placed at that point will effectively secure the waist and the thigh portions of the diaper simultaneously. However, in an adult, whose legs in the normal position are generally substantially parallel to each other and to the lateral line of the trunk of the wearer's body, a circle drawn at the edge of the garment about the wearer's thigh and substantially perpendicular to the wearer's thigh as defined hereinafter does not at any point approach a second circle drawn around the top portion of the garment secured about the wearer's waist or trunk. Thus, unlike prior art devices primarily designed to fit an infant, a single securement means on each side of the article will not serve to conform the garment to an adult wearer's waist while effectively securing the garment against leakage at the thigh area.
Second, as also revealed in the aforementioned Buell patent, it is desirable to construct an incontinent brief with elastics which are parallel to each other, and which lie along each edge of the crotch. This simplifies the manufacture of an incontinent brief, since the elastic can be applied in the machine direction when the article is manufactured. Brief elastics having a substantially straight-line contractable dimension have advantages in use as well. A substantially straight-line elastic member in the region of the crotch allows a single article to contract substantially along this dimension, so that the differing crotches of various individuals are accommodated to provide a snug fit of the article in the crotch area of the wearer. (This development of the prior art is in contrast to a great number of similar articles, such as conventional underwear, deploying elastic members which have no substantial straight-line element, and which generally conform around a cut-out in the brief.) However, a corresponding problem in prior art structures employing parallel straight-line elastic members having a substantially longitudinal contractable dimension and a single securement means to secure the waistband and legband portions, especially in an adult garment where the crotch width must necessarily be much less than the width of the portion of the garment which wraps around the trunk of the wearer, is that one cannot draw the functional ends of the straight-line elastic member effectively together around the thigh of the wearer to form a seal which is substantially perpendicular (as defined hereinafter) to the thigh bone of the wearer without unduly compromising the fit of the waistband portion about the wearer's trunk. As pointed out above, a seal which is not substantially perpendicular to the thigh bone of the wearer will not adequately contain the material which is to be absorbed or held by the brief.
In summary, devices can be found in the prior art which have straight-line elastic members on either side of the crotch; prior art structures having roughly the same can be found wherein a plurality of fasteners are used on either side of a garment to attach it to the body of a wearer. However, prior art is not available to solve the specific problems which are encountered when straight-line elastic members are used in a garment which requires a plurality of fastening means on either side of the body of the wearer in order to seal the garment to the thigh while providing a fit to the trunk of the wearer as well.